Nonwoven fibrous structures including ionic reinforcement material, and methods

ABSTRACT

Nonwoven fibrous structures and related media with ionic reinforcement material and methods of forming the same includes bonding at least a portion of the population of fibers together with an ionic reinforcement material. Nonwoven fibrous structures can be utilized as a mat, a web, a sheet, a scrim, or a combination thereof. Methods of making nonwoven fibrous structures and related media with ionic reinforcement material made according to the methods, are also disclosed.

TECHNICAL FIELD

The present disclosure relates to nonwoven fibrous structures andrelated media with ionic reinforcement material and methods of formingthe same.

BACKGROUND

Nonwoven fibrous webs have been used to produce a variety of absorbentarticles that are useful, for example, as absorbent wipes for surfacecleaning, as wound dressings, as gas and liquid absorbent or filtrationmedia, and as barrier materials for sound absorption.

SUMMARY

Although some methods of forming nonwoven fibrous webs are known, theart continually seeks new methods of forming and/or bonding nonwovenwebs, particularly air-laid nonwoven fibrous webs having particularcharacteristics with a relatively high cross direction (CD) tensilestrength and a relatively high machine direction (MD) tensile strength.

Thus, in one aspect, the present disclosure relates to a method ofmaking a nonwoven fibrous structure (e.g., a nonwoven fibrous web),including: introducing a plurality of fibers into a forming chamber,dispersing the fibers within the forming chamber to form a population ofindividual fibers suspended in a gas, collecting the population offibers as a nonwoven fibrous structure on a collector, and bonding atleast a portion of the population of fibers together with an ionicreinforcement material. In some exemplary embodiments, the methodcomprises applying an ionic liquid material to the population of fibers.In certain exemplary embodiments, the method includes bonding at leastthe portion of the population of fibers together comprises curing theapplied ionic liquid material to form the ionic reinforcement material.

In some exemplary embodiments, the applied ionic liquid material furthercomprises water, and where curing removes at least a portion of thewater from the applied ionic liquid material to cause bonding of theionic reinforcement material between the population of fibers. Incertain exemplary embodiments, the applied ionic liquid material furthercomprises at least one binder resin, optionally wherein the appliedionic liquid material acts as a plasticizer for the at least one binderresin. In some exemplary embodiments, the at least one binder resin isselected from the group consisting of a phenolic resin, a bio-basedresin, a thermoplastic (meth)acrylic (co)polymer resin, an epoxy resin,or a combination thereof. In certain exemplary embodiments, the methodincludes bonding with a binder resin mixture and the ionic liquidmaterial to provide a nonwoven fibrous structure with a tensile strengththat is greater than a nonwoven fibrous structure bonded with the binderresin mixture in the absence of the ionic liquid material.

In some exemplary embodiments, the ionic liquid material comprises atleast one cation and at least one anion. In certain exemplaryembodiments, the at least one cation is selected from the groupconsisting of nitrogen containing heterocyclic cations, ammonium,phosphonium, or sulfonium; and further wherein the at least one anion isselected from the group consisting of halogen anions, fluorinecontaining anions, alkyl sulfate anions, alkyl phosphate anions,acetate, dicyanamide (N(CN)₂), or thiocyanate (SCN). In some exemplaryembodiments, the method includes spraying the ionic liquid material,roll coating the ionic liquid material, dip coating the ionic liquidmaterial, or a combination thereof. In certain exemplary embodiments,the ionic liquid material is an ionic liquid solution in a solvent,optionally wherein the solvent is aqueous.

In some exemplary embodiments, bonding at least the portion of thepopulation of fibers together includes applying a thermosetting binderto the population fibers. In certain exemplary embodiments, bonding atleast the portion of the population of fibers includes heating theportion of the population of fibers. In some exemplary embodiments, theionic reinforcement material provides at least one distinguishingcharacteristic to the nonwoven fibrous structure selected from the groupconsisting of a fire retardant characteristic, an antistaticcharacteristic, an antibacterial characteristic, an antimicrobialcharacteristic, an antifungal characteristic, or a combination thereof.In certain exemplary embodiments, the population of fibers includesfibers selected from the group consisting of staple fibers, melt blownfibers, natural fibers, bio-based fibers, or a combination thereof.

In certain exemplary embodiments, the nonwoven fibrous structureincludes a population of particulates bonded to the nonwoven fibrousstructure, further wherein the particulates are selected from the groupconsisting of abrasive particulates, detergent particulates,anti-bacterial particulates, adsorbent particulates, absorbentparticulates, or a combination thereof. In some exemplary embodiments,the nonwoven fibrous structure is a structure selected from the groupconsisting of a mat, a web, a sheet, a scrim, or a combination thereof.

The disclosure also relates to a nonwoven fibrous web prepared accordingto the method described herein. In addition, the disclosure relates to anonwoven fibrous structure comprising a population of randomly orientedfibers bonded together at a plurality of intersection points with anionic reinforcement material. In some exemplary embodiments, the ionicreinforcement material is comprised of an ionic plasticizer (e.g., ionicliquid acting as a plasticizer). In certain exemplary embodiments, theionic reinforcement material is comprised of an ionic liquid and abinder selected from the group consisting of a (meth)acrylic (co)polymerbinder, a styrene-butadiene latex binder, a bio-based binder, or acombination thereof. In some exemplary embodiments, the nonwoven fibrousstructure comprises from 1 to 40 wt. % of the ionic liquid. In furtherembodiments, the ionic liquid comprises water, one or more cations, andone or more anions.

In some exemplary embodiments, the nonwoven fibrous structure exhibitsat least one distinguishing characteristic selected from the groupconsisting of a fire retardant characteristic, an antistaticcharacteristic, an antibacterial characteristic, an antimicrobialcharacteristic, an antifungal characteristic, or a combination thereof.In certain exemplary embodiments, the ionic reinforcement materialprovides the at least one distinguishing characteristic. In someexemplary embodiments, the ionic reinforcement material provides atleast two of the distinguishing characteristics. In certain exemplaryembodiments, the population of fibers includes thermoplastic (co)polymerfibers further comprising a (co)polymer selected from poly(propylene),poly(ethylene), poly(butane), poly(ethylene) terephthalate,poly(butylene) terephthalate, poly(ethylene) napthalate, poly(amide),poly(urethane), poly(lactic acid), poly(vinyl)alcohol, poly(phenylene)sulfide, poly(sulfone), liquid crystalline polymer,poly(ethylene)-co-poly(vinyl)acetate, poly(acrylonitrile), cyclicpoly(olefin), poly(oxymethylene), poly(olefinic) thermoplasticelastomers, recycled fibers containing any of the precedingthermoplastic (co)polymers, or a combination thereof.

In some exemplary embodiments, the population of fibers includes naturalfibers selected from cotton, wool, jute, agave, sisal, coconut, soybean,hemp, viscose, bamboo, or a combination thereof. In certain exemplaryembodiments, the nonwoven fibrous structure includes a population ofparticulates bonded to the nonwoven fibrous structure, further whereinthe particulates are selected from the group consisting of abrasiveparticulates, detergent particulates, anti-bacterial particulates,adsorbent particulates, absorbent particulates; or a combinationthereof. In some exemplary embodiments, the population of particulatesexhibits a median particle diameter of from 0.1 micrometer to 1,000micrometers. In certain exemplary embodiments, the population of fibersexhibits a median fiber diameter of from 1 micrometer to 50 micrometers.In some exemplary embodiments, the nonwoven fibrous structure is astructure selected from the group consisting of a mat, a web, a sheet, ascrim, or a combination thereof.

Various exemplary embodiments of the present disclosure are furtherillustrated by the following listing of exemplary embodiments, whichshould not be construed to unduly limit the present disclosure:

LISTING OF EXEMPLARY EMBODIMENTS

-   -   A. A method of making a nonwoven fibrous structure, comprising:        -   a. introducing a plurality of fibers into a forming chamber;        -   b. dispersing the fibers within the forming chamber to form            a population of individual fibers suspended in a gas;        -   c. collecting the population of fibers as a nonwoven fibrous            structure on a collector; and        -   d. bonding at least a portion of the population of fibers            together with an ionic reinforcement material.    -   B. The method of embodiment A, further comprising applying an        ionic liquid material to the population of fibers.    -   C. The method of embodiment B, wherein bonding at least the        portion of the population of fibers together comprises curing        the applied ionic liquid material to form the ionic        reinforcement material.    -   D. The method of embodiment C, wherein the applied ionic liquid        material further comprises water, and further wherein curing        removes at least a portion of the water from the applied ionic        liquid material to cause bonding of the ionic reinforcement        material between the population of fibers.    -   E. The method of any one of embodiments B-D, wherein the applied        ionic liquid material further comprises at least one binder        resin, optionally wherein the applied ionic liquid material acts        as a plasticizer for the at least one binder resin.    -   F. The method of embodiment E, wherein the at least one binder        resin is selected from the group consisting of a phenolic resin,        a bio-based resin, a thermoplastic (meth)acrylic (co)polymer        resin, an epoxy resin, or a combination thereof    -   G. The method of any one of embodiments B-F, wherein bonding        includes bonding with a binder resin mixture and the ionic        liquid material to provide a nonwoven fibrous structure with a        tensile strength that is greater than a nonwoven fibrous        structure bonded with the binder resin mixture in the absence of        the ionic liquid material.    -   H. The method of any one of embodiments B-G, wherein the ionic        liquid material comprises at least one cation and at least one        anion.    -   I. The method of any one of embodiments B-H, wherein the at        least one cation is selected from the group consisting of        nitrogen containing heterocyclic cations, ammonium, phosphonium,        or sulfonium; and further wherein the at least one anion is        selected from the group consisting of halogen anions, fluorine        containing anions, alkyl sulfate anions, alkyl phosphate anions,        acetate, dicyanamide (N(CN)₂), or thiocyanate (SCN).    -   J. The method of any one of embodiments B-I, wherein applying        the ionic liquid material consists of spraying the ionic liquid        material, roll coating the ionic liquid material, dip coating        the ionic liquid material, or a combination thereof    -   K. The method of any one of embodiments B-J, wherein the ionic        liquid material is an ionic liquid solution in a solvent,        optionally wherein the solvent is aqueous.    -   L. The method of any one of embodiments A-K, wherein bonding at        least the portion of the population of fibers together includes        applying a thermosetting binder to the population fibers.    -   M. The method of any one of embodiments A-L, wherein bonding at        least the portion of the population of fibers includes heating        the portion of the population of fibers.    -   N. The method of any one of embodiments A-M, wherein the ionic        reinforcement material provides at least one distinguishing        characteristic to the nonwoven fibrous structure selected from        the group consisting of a fire retardant characteristic, an        antistatic characteristic, an antibacterial characteristic, an        antimicrobial characteristic, an antifungal characteristic, or a        combination thereof.    -   O. The method of any one of embodiments A-N, wherein the        population of fibers includes fibers selected from the group        consisting of mono-component fibers, multi-component fibers,        crimped fibers, or a combination thereof.    -   P. The method of any one of embodiments A-O, wherein the        population of fibers includes fibers selected from the group        consisting of staple fibers, melt blown fibers, natural fibers,        bio-based fibers, or a combination thereof    -   Q. The method of any one of embodiments A-P, wherein the        nonwoven fibrous structure includes a population of particulates        bonded to the nonwoven fibrous structure, further wherein the        particulates are selected from the group consisting of abrasive        particulates, detergent particulates, anti-bacterial        particulates, adsorbent particulates, absorbent particulates, or        a combination thereof    -   R. The method of any one of embodiments A-Q, wherein the        nonwoven fibrous structure is a structure selected from the        group consisting of a mat, a web, a sheet, a scrim, or a        combination thereof    -   S. A nonwoven fibrous structure prepared according to the method        of any one of embodiments A-R.    -   T. A nonwoven fibrous structure comprising:        -   a. a population of randomly oriented fibers bonded together            at a plurality of intersection points with an ionic            reinforcement material.    -   U. The nonwoven fibrous structure of embodiment T, wherein the        ionic reinforcement material is comprised of an ionic        plasticizer.    -   V. The nonwoven fibrous structure of embodiment T or U, wherein        the ionic reinforcement material is comprised of an ionic liquid        and a binder selected from the group consisting of a        (meth)acrylic (co)polymer binder, a styrene-butadiene latex        binder, a bio-based binder, or a combination thereof.    -   W. The nonwoven fibrous structure of embodiment V, comprising        from 1 to 40 wt. % of the ionic liquid.    -   X. The nonwoven fibrous structure of any one of embodiments V-W,        wherein the ionic liquid comprises water, one or more cations,        and one or more anions.    -   Y. The nonwoven fibrous structure of any one of embodiments T-X,        exhibiting at least one distinguishing characteristic selected        from the group consisting of a fire retardant characteristic, an        antistatic characteristic, an antibacterial characteristic, an        antimicrobial characteristic, an antifungal characteristic, or a        combination thereof.    -   Z. The nonwoven fibrous structure of embodiment Y, wherein the        ionic reinforcement material provides the at least one        distinguishing characteristic.    -   AA. The nonwoven fibrous structure of any one of embodiments        T-Z, wherein the population of fibers includes fibers selected        from the group consisting of mono-component fibers,        multi-component fibers, crimped fibers, or a combination thereof    -   BB. The nonwoven fibrous structure of any one of embodiments        T-AA, wherein the population of fibers includes fibers selected        from the group consisting of staple fibers, melt blown fibers,        natural fibers, or a combination thereof    -   CC. The nonwoven fibrous structure of any one of embodiments        T-BB, wherein the population of fibers includes thermoplastic        (co)polymer fibers further comprising a (co)polymer selected        from poly(propylene), poly(ethylene), poly(butane),        poly(ethylene) terephthalate, poly(butylene) terephthalate,        poly(ethylene) napthalate, poly(amide), poly(urethane),        poly(lactic acid), poly(vinyl)alcohol, poly(phenylene) sulfide,        poly(sulfone), liquid crystalline polymer,        poly(ethylene)-co-poly(vinyl)acetate, poly(acrylonitrile),        cyclic poly(olefin), poly(oxymethylene), poly(olefinic)        thermoplastic elastomers, recycled fibers containing any of the        preceding thermoplastic (co)polymers, or a combination thereof    -   DD. The nonwoven fibrous structure of any one of embodiments        T-CC, wherein the population of fibers includes natural fibers        selected from cotton, wool, jute, agave, sisal, coconut,        soybean, hemp, viscose, bamboo, or a combination thereof    -   EE. The nonwoven fibrous structure of any one of embodiments        T-DD, wherein the nonwoven fibrous structure includes a        population of particulates bonded to the nonwoven fibrous        structure, further wherein the particulates are selected from        the group consisting of abrasive particulates, detergent        particulates, anti-bacterial particulates, adsorbent        particulates, absorbent particulates; or a combination thereof    -   FF. The nonwoven fibrous structure of any one of embodiments        T-EE, wherein the population of particulates exhibits a median        particle diameter of from 0.1 micrometer to 1,000 micrometers.    -   GG. The nonwoven fibrous structure of any one of embodiments        T-FF, wherein the population of fibers exhibits a median fiber        diameter of from 1 micrometer to 50 micrometers.    -   HH. The nonwoven fibrous structure of any one of embodiments        T-GG, wherein the nonwoven fibrous structure is a structure        selected from the group consisting of a mat, a web, a sheet, a        scrim, or a combination thereof.

Various aspects and advantages of embodiments of the presently disclosedinvention have been summarized. The above Summary is not intended todescribe each illustrated embodiment or every implementation of thepresently disclosed invention. The Drawings and the Detailed Descriptionthat follow more particularly exemplify certain preferred embodimentsusing the principles disclosed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the present disclosure are further describedwith reference to the appended figures, wherein:

FIG. 1 is a perspective view of an exemplary nonwoven fibrous structureof the present disclosure.

FIG. 2 is an exploded view of a portion of the exemplary nonwovenfibrous structure of FIG. 1, illustrating one exemplary embodiment ofthe present disclosure.

DETAILED DESCRIPTION

As used in this specification and the appended embodiments, the singularforms “a”, “an”, and “the” include plural referents unless the contentclearly dictates otherwise. Thus, for example, reference to fine fiberscontaining “a compound” includes a mixture of two or more compounds. Asused in this specification and the appended embodiments, the term “or”is generally employed in its sense including “and/or” unless the contentclearly dictates otherwise.

As used in this specification, the recitation of numerical ranges byendpoints includes all numbers subsumed within that range (e.g. 1 to 5includes 1, 1.5, 2, 2.75, 3, 3.8, 4, and 5).

Unless otherwise indicated, all numbers expressing quantities oringredients, measurement of properties and so forth used in thespecification and embodiments are to be understood as being modified inall instances by the term “about.” Accordingly, unless indicated to thecontrary, the numerical parameters set forth in the foregoingspecification and attached listing of embodiments can vary dependingupon the desired properties sought to be obtained by those skilled inthe art utilizing the teachings of the present disclosure. At the veryleast, and not as an attempt to limit the application of the doctrine ofequivalents to the scope of the claimed embodiments, each numericalparameter should at least be construed in light of the number ofreported significant digits and by applying ordinary roundingtechniques.

For the following Glossary of defined terms, these definitions shall beapplied for the entire application, unless a different definition isprovided in the claims or elsewhere in the specification.

GLOSSARY

“Nonwoven fibrous web” or “nonwoven fibrous structure” means an articleor sheet having a structure of individual fibers or fibers, which areinterlaid, but not in an identifiable manner as in a knitted fabric.Nonwoven fabrics or webs have been formed from many processes such asfor example, meltblowing processes, air-laying processes, and bondedcarded web processes.

“Die” means a processing assembly for use in polymer melt processing andfiber extrusion processes, including but not limited to meltblowing andspun-bonding.

“Meltblowing” and “meltblown process” means a method for forming anonwoven fibrous web by extruding a molten fiber-forming materialthrough a plurality of orifices in a die to form fibers while contactingthe fibers with air or other attenuating fluid to attenuate the fibersinto fibers, and thereafter collecting the attenuated fibers. Anexemplary meltblowing process is taught in, for example, U.S. Pat. No.6,607,624 (Berrigan et al.).

“Meltblown fibers” means fibers prepared by a meltblowing or meltblownprocess.

“Spun-bonding” and “spun bond process” mean a method for forming anonwoven fibrous structure by extruding molten fiber-forming material ascontinuous or semi-continuous fibers from a plurality of finecapillaries of a spinneret, and thereafter collecting the attenuatedfibers. An exemplary spun-bonding process is disclosed in, for example,U.S. Pat. No. 3,802,817 to Matsuki et al.

“Spun bond fibers” and “spun-bonded fibers” mean fibers made usingspun-bonding or a spun bond process. Such fibers are generallycontinuous fibers and are entangled or point bonded sufficiently to forma cohesive nonwoven fibrous web such that it is usually not possible toremove one complete spun bond fiber from a mass of such fibers. Thefibers may also have shapes such as those described, for example, inU.S. Pat. No. 5,277,976 to Hogle et al., which describes fibers withunconventional shapes.

“Carding” and “carding process” mean a method of forming a nonwovenfibrous web webs by processing staple fibers through a combing orcarding unit, which separates or breaks apart and aligns the staplefibers in the machine direction to form a generally machine directionoriented fibrous nonwoven web. An exemplary carding process is taughtin, for example, U.S. Pat. No. 5,114,787 to Chaplin et al.

“Bonded carded web” refers to nonwoven fibrous web formed by a cardingprocess wherein at least a portion of the fibers are bonded together bymethods that include for example, thermal point bonding, autogenousbonding, hot air bonding, ultrasonic bonding, needle punching,calendering, application of a spray adhesive, and the like.

“Calendering” means a process of passing a nonwoven fibrous web throughrollers with application of pressure to obtain a compressed and bondedfibrous nonwoven web. The rollers may optionally be heated.

“Densification” means a process whereby fibers which have been depositedeither directly or indirectly onto a filter winding arbor or mandrel arecompressed, either before or after the deposition, and made to form anarea, generally or locally, of lower porosity, whether by design or asan artifact of some process of handling the forming or formed filter.Densification also includes the process of calendering webs.

“Non-hollow” with particular reference to projections extending from amajor surface of a nonwoven fibrous structure means that the projectionsdo not contain an internal cavity or void region other than themicroscopic voids (i.e. void volume) between randomly oriented discretefibers.

“Randomly oriented” with particular reference to a population of fibersmeans that the fiber bodies are not substantially aligned in a singledirection.

“Air-laying” is a process by which a nonwoven fibrous web layer can beformed. In the air-laying process, bundles of small fibers havingtypical lengths ranging from about 3 to about 52 millimeters (mm) areseparated and entrained in an air supply and then deposited onto aforming screen, usually with the assistance of a vacuum supply. Therandomly oriented fibers may then be bonded to one another using, forexample, thermal point bonding, autogenous bonding, hot air bonding,needle punching, calendering, a spray adhesive, and the like. Anexemplary air-laying process is taught in, for example, U.S. Pat. No.4,640,810 to Laursen et al.

“Particulate loading” or a “particle loading process” means a process inwhich particulates are added to a fiber stream or web while it isforming. Exemplary particulate loading processes are taught in, forexample, U.S. Pat. No. 4,818,464 to Lau and U.S. Pat. No. 4,100,324 toAnderson et al.

“Particulate” and “particle” are used substantially interchangeably.Generally, a particulate or particle means a small distinct piece orindividual part of a material in finely divided form. However, aparticulate may also include a collection of individual particlesassociated or clustered together in finely divided form. Thus,individual particulates used in certain exemplary embodiments of thepresent disclosure may clump, physically intermesh, electro-staticallyassociate, or otherwise associate to form particulates. In certaininstances, particulates in the form of agglomerates of individualparticulates may be intentionally formed such as those described in U.S.Pat. No. 5,332,426 (Tang et al.).

“Layer” means a single stratum formed between two major surfaces. Alayer may exist internally within a single web, e.g., a single stratumformed with multiple strata in a single web having first and secondmajor surfaces defining the thickness of the web. A layer may also existin a composite article comprising multiple webs, e.g., a single stratumin a first web having first and second major surfaces defining thethickness of the web, when that web is overlaid or underlaid by a secondweb having first and second major surfaces defining the thickness of thesecond web, in which case each of the first and second webs forms atleast one layer. In addition, layers may simultaneously exist within asingle web and between that web and one or more other webs, each webforming a layer.

“Particulate density gradient,” “sorbent density gradient,” and “fiberpopulation density gradient” mean that the amount of particulate,sorbent or fibrous material within a particular fiber population (e.g.,the number, weight or volume of a given material per unit volume over adefined area of the web) need not be uniform throughout the nonwovenfibrous web, and that it can vary to provide more material in certainareas of the web and less in other areas.

Various exemplary embodiments of the disclosure will now be describedwith particular reference to the Drawings. Exemplary embodiments of theinvention may take on various modifications and alterations withoutdeparting from the spirit and scope of the disclosure. Accordingly, itis to be understood that the embodiments of the invention are not to belimited to the following described exemplary embodiments, but is to becontrolled by the limitations set forth in the claims and anyequivalents thereof.

Nonwoven fibrous structures (e.g., nonwoven fibrous webs, etc.) have aplurality of applications (e.g., uses) including: cleaning applications,filtration applications, and/or textile applications, among others.Nonwoven fibrous structures can be better suited to particularapplications when the nonwoven fibrous structure exhibits particularcharacteristics (e.g., fire retardant characteristics, antistaticcharacteristics, antibacterial characteristics, antimicrobialcharacteristics, antifungal characteristics, etc.). The presentdisclosure describes nonwoven fibrous structures that include a portionof a population of fibers that are bonded together with an ionicreinforcement material and methods of making the same. The ionicreinforcement material provides an increase in the tensile strength ofthe nonwoven fibrous structure as well as provides a number ofcharacteristics. In some exemplary embodiments, the ionic reinforcementmaterial provides a plurality of characteristics as described herein.

As described further herein, the ionic reinforcement material can beapplied to the nonwoven fibrous structure utilizing an application of anionic liquid material. The ionic liquid material can include an ionicliquid (e.g., liquid comprising at least one cation and at least oneanion). The ionic liquid material applied to the nonwoven fibrousstructure can be cured to bind a portion of the population of fibers ofthe nonwoven fibrous structure with an ionic reinforcement material.

FIG. 1 is a perspective view of one exemplary embodiment of a nonwovenfibrous structure 234 (e.g., air-laid nonwoven fibrous web, melt-spunnonwoven fibrous web, carded nonwoven fibrous web, etc.) comprising aplurality of randomly oriented fibers according to the presentdisclosure. In some exemplary embodiments, the nonwoven fibrousstructure is a structure selected from the group consisting of a mat, aweb, a sheet, a scrim, or a combination thereof.

In some optional embodiments, the present disclosure describes anonwoven fibrous structure comprising a plurality of randomly orientedfibers 2, the nonwoven fibrous structure further comprising a pluralityof optional non-hollow projections 200 extending from a major surface204 of the nonwoven fibrous structure (as considered without theprojections), and a plurality of substantially planar land areas 202formed between each adjoining projection 200 in a plane defined by andsubstantially parallel with the major surface 204.

In some exemplary embodiments, the randomly oriented discrete fibers 2can include fibers 120 selected from the group consisting ofmono-component fibers, multi-component fibers, crimped fibers, or acombination thereof. In certain exemplary embodiments, the randomlyoriented discrete fibers 2 can include fibers selected from the groupconsisting of staple fibers, melt blown fibers, natural fibers, or acombination thereof. In some exemplary embodiments, the randomlyoriented discrete fibers 2 can include natural fibers selected fromcotton, wool, jute, agave, sisal, coconut, soybean, hemp, viscose,bamboo, or a combination thereof. In certain exemplary embodiments, therandomly oriented discrete fibers 2 can include fibers that exhibit amedian fiber diameter of from 1 micrometer to 50 micrometers.

In some exemplary embodiments, the randomly oriented discrete fibers 2can include thermoplastic (co)polymer fibers further comprising a(co)polymer selected from poly(propylene), poly(ethylene), poly(butane),poly(ethylene) terephthalate, poly(butylene) terephthalate,poly(ethylene) napthalate, poly(amide), poly(urethane), poly(lacticacid), poly(vinyl)alcohol, poly(phenylene) sulfide, poly(sulfone),liquid crystalline polymer, poly(ethylene)-co-poly(vinyl)acetate,poly(acrylonitrile), cyclic poly(olefin), poly(oxymethylene),poly(olefinic) thermoplastic elastomers, recycled fibers containing anyof the preceding thermoplastic (co)polymers, or a combination thereof.

The randomly oriented discrete fibers 2 may, in some exemplaryembodiments, optionally include filling fibers 110. The filling fibers110 are any fiber other than a multi-component fiber. The optionalfilling fibers 110 are preferably mono-component fibers, which may bethermoplastic or “melty” fibers. In certain exemplary embodiments, thefilling fibers can include bio-based fibers. Bio-based fibers caninclude natural fibers and/or biodegradable fibers. For example, theoptional filling fibers 110 may, in some exemplary embodiments, comprisenatural fibers, more preferably natural fibers derived from renewablesources, and/or incorporating recycled materials. Non-limiting examplesof suitable natural fibers include those of bamboo, cotton, wool, jute,agave, sisal, coconut, sawgrass, soybean, hemp, and the like. Cellulosicfibers (e.g., cellulose, cellulose acetate, cellulose triacetate, rayon,and the like) may be particularly well-suited natural fibers. The fibercomponent used may be virgin fibers or recycled waste fibers, forexample, recycled fibers reclaimed from garment cuttings, carpetmanufacturing, fiber manufacturing, textile processing, paper, reclaimedwood, or the like. In another example, the optional filling fibers 110are biodegradable fibers. The biodegradable fibers can include, but arenot limited to fibers comprising a substantial amount of aliphaticpolyester (co)polymer derived from poly(lactic acid), poly (glycolicacid), poly (lactic-co-glycolic acid) blends, and/or a combinationthereof. In some presently preferred embodiments, at least some of thefilling fibers 120 may be bonded to at least a portion of the discretefibers 2 at a plurality of intersection points with the first region 112of the multi-component fibers 110.

In some exemplary embodiments of the previously described nonwovenfibrous structure, the nonwoven fibrous structure 234 may optionallyinclude a plurality of particulates 130 as shown in FIG. 2. FIG. 2illustrates an exploded view of region 2 of the nonwoven fibrousstructure 234 of FIG. 1, shown comprising randomly oriented discretefibers 2 and a plurality of optional particulates 130.

In some exemplary embodiments, the optional particulates 130 can beparticulates selected from the group consisting of abrasiveparticulates, detergent particulates, anti-bacterial particulates,adsorbent particulates, absorbent particulates, or a combinationthereof. In certain exemplary embodiments, the optional population ofparticulates 130 can exhibit a median particle diameter of from 0.1micrometer to 1,000 micrometers. The optional particulates 130 can beapplied at various stages of the forming process for the nonwovenfibrous structure 234. In one example, the optional particulates can beapplied by a particulate loading process. Exemplary particulate loadingprocesses are taught in, for example, U.S. Pat. Nos. 4,818,464 and4,100,324.

Additionally, in some particular exemplary embodiments, an input streammay advantageously be located to introduce particulates 130 in a mannersuch that the particulates 130 are distributed substantially uniformlythroughout the nonwoven fibrous structure 234. Alternatively, in someparticular exemplary embodiments, an input stream may advantageously belocated to introduce particulates 130 in a manner such that theparticulates 130 are distributed substantially at a major surface of thenonwoven fibrous structure 234, for example, proximate a lower majorsurface of nonwoven fibrous structure 234, or proximate the upper majorsurface of the nonwoven fibrous structure 234.

In certain exemplary embodiments, a binder can be applied to thenonwoven fibrous structure 234 and may provide further strength to thenonwoven fibrous structure 234, may further secure the particulates 130to the fibers of the nonwoven fibrous structure 234, and/or may provideadditional stiffness for an abrasive or scouring article. The bindercoating may be applied by known processing means such as roll coating,spray coating, and immersion coating and combinations of these coatingtechniques. The binder coating may include additional particulates 130within the binder or additional particulates 130 may be incorporated andsecured to the binder.

In exemplary embodiments, an ionic liquid material (e.g., ionic liquidmixture) can be coated on the nonwoven fibrous structure 234. The ionicliquid material can include an ionic liquid (e.g., liquid that comprisesat least one cation and at least one anion, aqueous solution thatcomprises at least one cation and at least one anion). That is, theionic liquid material is an ionic liquid solution in a solvent,optionally the solvent is aqueous. In some exemplary embodiments, theionic liquid can include at least one cation that is selected from thegroup containing heterocyclic cations, ammonium, phosphonium, orsulfonium. In addition, in certain exemplary embodiments, the ionicliquid can include at least one anion that is selected from the groupconsisting of halogen anions, fluorine containing anions, alkyl sulfateanions, alkyl phosphate anions, acetate, dicyanamide (N(CN)₂), orthiocyanate (SCN). The ionic liquid can be comprised of a salt dissolvedin a liquid. For example, the ionic liquid material can comprise a saltdissolved in water to produce an ionic liquid that comprises at leastone cation and at least one anion in an aqueous solution. For example,the ionic liquid material can comprise a salt dissolved in water toproduce an ionic liquid that comprises at least one cation and at leastone anion in an aqueous solution. In some exemplary embodiments, theionic liquid can include at least one of the ionic liquids from thegroup of: sodium chloride (NaCl), choline dihydrogen phosphate,1-ethyl-3-methylimidazolium ethyl phosphate, 1-ethyl-3-methylimidazoliumethyl sulfate, 1-ethyl-3-methylimidazolium acetate,1-ethyl-3-methylimidazolium triflate, or 1-ethyl-3-methylimidazoliumdicyanamide.

The ionic liquid material may be applied by known processing means suchas roll coating, spray coating, and immersion coating and combinationsof these coating techniques. In some exemplary embodiments, the ionicliquid material is introduced as a mist from an atomizer within aforming chamber. In certain exemplary embodiments, the ionic liquidmaterial wets the fibers so that particulates cling to the surface ofthe fibers.

In some exemplary embodiments, the ionic liquid material can alsoinclude a binder. The binder may comprise a resin. Suitable resinsinclude phenolic resins, a bio-based resin, a thermoplastic(meth)acrylic (co)polymer resin, an epoxy resin, polyurethane resins,polyureas, styrene-butadiene rubbers, nitrile rubbers, epoxies,acrylics, and polyisoprene. The binder may be water soluble. Examples ofwater soluble binders include surfactants, polyethylene glycol,polyvinylpyrrolidones, polylactic acid (PLA), polyvinylpyrrolidone/vinylacetate copolymers, polyvinyl alcohols, carboxymethyl celluloses,hydroxypropyl cellulose starches, polyethylene oxides, polyacrylamides,polyacrylic acids, cellulose ether polymers, polyethyl oxazolines,esters of polyethylene oxide, esters of polyethylene oxide andpolypropylene oxide copolymers, urethanes of polyethylene oxide, andurethanes of polyethylene oxide and polypropylene oxide copolymers.

In embodiments where the ionic liquid material includes the binder, theionic liquid material can include from 1 to 40 weight percent (wt. %) ofan ionic liquid and a binder in a liquid mixture (e.g., liquid solution,aqueous solution, etc.). In certain exemplary embodiments, the ionicliquid material can include from 1 to 10 wt. % of an ionic liquid and abinder in a liquid mixture. That is, the ionic liquid material caninclude a particular weight percent of ionic liquid, a binder asdescribed herein, and/or a percentage of water. Thus, the ionic liquidmaterial can include the ionic liquid and the binder as a mixture and/orsolution and applied by known processing means such as roll coating,spray coating, and immersion coating and combinations of these coatingtechniques.

In embodiments where the ionic liquid material includes the binder, theionic liquid can act as a plasticizer for the binder in the ionic liquidmaterial. That is, the ionic liquid can increase the elongation (e.g.,plasticity, fluidity) of the resulting nonwoven fibrous structure 234.In some exemplary embodiments, an increase in elongation of the nonwovenfibrous structure 234 occurs in the machine direction (MD). In certainexemplary embodiments, the increase in elongation of the nonwovenfibrous structure 234 occurs in the transverse direction (TD). In someexemplary embodiments, the increase in elongation of the air laidnonwoven fibrous structure occurs in both the machine direction (MD) andthe transverse direction (TD).

In certain exemplary embodiments, the ionic liquid material is comprisedof an ionic liquid and a binder selected from the group consisting of a(meth)acrylic (co)polymer binder, a styrene-butadiene latex binder, abio-based binder, or a combination thereof. In a specific embodiment, aliquid mixture (e.g., liquid solution) of ionic liquid cholinedihydrogen phosphate can be added to a binder from the group asdescribed herein (e.g., thermosetting binder, Acrodur thermosettingbinder from BASF chemical company). In this specific embodiment, thethermosetting binder can be a binder that is relatively brittle whencured (e.g., heat is applied to the binder, etc.). As described herein,the addition of the ionic liquid choline dihydrogen phosphate has aplasticizing effect (e.g., acts as a plasticizer) on the thermosettingbinder. That is, the nonwoven fibrous structure 234 is less brittle withthe addition of the ionic liquid choline dihydrogen phosphate andthermosetting binder compared to a nonwoven fibrous structure with theaddition of the thermosetting binder and no ionic liquid.

A number of devices can be utilized to remove excess liquid (e.g.,water) from the nonwoven fibrous structure 234. In some exemplaryembodiments calendering can be utilized to remove liquid from thenonwoven fibrous structure 234. Calendering can include a process ofpassing a nonwoven fibrous web through rollers with application ofpressure to obtain a compressed and bonded fibrous nonwoven web. Incertain exemplary embodiments, the number of devices can include anumber of squeegees that can compress the nonwoven fibrous structure 234and remove a portion of the liquid (e.g., water) that is applied to thenonwoven fibrous structure 234. In certain exemplary embodiments, thenumber of squeegees can be utilized before the nonwoven fibrousstructure 234 is moved to a heating unit (e.g., oven, etc.) to removeliquid that was not removed by the number of squeegees. In otherembodiments, the number of devices can be located at various points ofthe formation process of the nonwoven fibrous structure 234.

The heating unit can also be utilized for curing the ionic liquidmaterial applied to the nonwoven fibrous structure 234. In someexemplary embodiments, the binder in the ionic liquid material is athermosetting binder (e.g., a binder resin that hardens under heatedconditions, etc.), wherein the binder and the ionic liquid of the ionicliquid material is cured with the heating unit. In addition, the heatingunit can be utilized to remove liquid (e.g., water) that exists onand/or within the nonwoven fibrous structure 234. As described herein,the heating unit can remove liquid that remains after a number ofdevices are utilized to remove liquid. Removing the liquid can producean ionic reinforcement material at locations where the ionic liquidmaterial was applied to the nonwoven fibrous structure 234.

The ionic liquid material can bond a portion of the population of fiberswith an ionic reinforcement material. In some exemplary embodiments, theionic reinforcement material is a residual material of the ionic liquidmaterial (e.g., material remaining after liquid is removed from theionic liquid material). That is, in some exemplary embodiments, theionic reinforcement material is the residual of the ionic liquidmaterial after the liquid (e.g., water, excess water) is removed fromthe nonwoven fibrous structure 234. The ionic reinforcement material canprovide an adhesive bond between the portion of the population of fiberswhen a binder is included in the ionic liquid material, as describedherein.

The ionic reinforcement material can provide a number of characteristicsto the nonwoven fibrous structure 234. The ionic reinforcement materialcan provide the number of characteristics when the ionic reinforcementmaterial includes the ionic liquid or the ionic liquid and bindermixture as described herein. In some exemplary embodiments, the numberof characteristics can include a fire retardant characteristic, anantistatic characteristic, an antibacterial characteristic, anantimicrobial characteristic, an antifungal characteristic, or acombination thereof. In certain exemplary embodiments, the ionicreinforcement material provides at least one of the number ofcharacteristics. In some exemplary embodiments, the ionic reinforcementmaterial provides a plurality of the number of characteristics asdescribed herein. In some exemplary embodiments, the ionic reinforcementmaterial can provide at least two of the number of characteristicslisted herein.

In one exemplary embodiment, the ionic reinforcement material is appliedto the nonwoven fibrous structure 234 with an ionic liquid materialcomprising the ionic liquid choline dihydrogen phosphate and athermosetting binder. In this exemplary embodiment, the nonwoven fibrousstructure 234 is less brittle with the addition of the ionic liquidcholine dihydrogen phosphate and thermosetting binder compared to anonwoven fibrous structure 234 with only the addition of thethermosetting binder. In addition, the nonwoven fibrous structure 234comprises antistatic characteristics from the ionic reinforcementmaterial. As described further herein, the addition of the ionic liquidcholine dihydrogen phosphate and thermosetting binder to the nonwovenfibrous structure 234 can provide additional fire retardant (e.g., flameretardant) characteristics to nonwoven fibrous structure 234. The ionicreinforcement material can also add additional characteristics that caninclude: a fire retardant characteristic, an antistatic characteristic,an antibacterial characteristic, an antimicrobial characteristic, anantifungal characteristic, or a combination thereof.

As described herein, the ionic reinforcement material can increase theelongation (e.g., plasticity or fluidity) of the nonwoven fibrousstructure 234. The ionic reinforcement material can also provide anincrease in a tensile strength of the nonwoven fibrous structure 234. Insome exemplary embodiments the ionic reinforcement material can providean increase in a tensile strength of the nonwoven fibrous structure 234and an increase in elongation of the nonwoven fibrous structure 234. Insome exemplary embodiments, the increase in tensile strength and theincrease in elongation are in the machine direction (MD) of the nonwovenfibrous structure 234.

A nonwoven fibrous structure 234 (e.g., fibrous web, air-laid nonwovenfibrous web, etc.) according to the present disclosure can be formedutilizing a number of forming methods (e.g., melt-spinning, air-laying,spun-bonding, carding, etc.). In exemplary embodiments, the nonwovenfibrous structure 234 is formed by air-laying fiber processingequipment, such as shown and described in U.S. Pat. Nos. 7,491,354 and6,808,664.

In some exemplary embodiments, the air laying fiber processing equipmentcan use air flow to mix and inter-engage the fibers to form an air laidnonwoven fibrous structure. That is, the air laid nonwoven fibrousstructure is formed by introducing a plurality of fibers into a formingchamber and dispersing the fibers within the forming chamber to form apopulation of individual fibers suspended in a gas, wherein the fibersare allowed to fall down to a collector.

In particular embodiments, instead of using strong air flow to mix andinter-engaged the fibers to form an air-laid nonwoven fibrous structure(such as with a “RandoWebber” web forming machine, available from RandoMachine Corporation, Macedon, N.Y.), the forming chamber can have spikerollers to blend and mix the fibers while gravity allows the fibers tofall down through the endless belt screen and form an air-laid nonwovenfibrous structure of inter-engaged fibers. With this construction ofair-laying equipment, the fibers and the particulates are, in someexemplary embodiments, falling together to the bottom of the formingchamber to form the air-laid nonwoven fibrous structure. In oneexemplary embodiment, a vacuum can be included below the area where theair-laid nonwoven fibrous structure forms in the forming chamber.

In some exemplary embodiments, the nonwoven fibrous structure 234 isformed using a carding process. An exemplary carding process is taughtin, for example, U.S. Pat. No. 5,114,787. In some exemplary embodiments,the nonwoven fibrous structure 234 is formed by a meltblowing process.The meltblowing process is a method for forming a nonwoven fibrousstructure by extruding a molten fiber-forming material through aplurality of orifices in a die to form fibers while contacting thefibers with air or other attenuating fluid to attenuate the fibers intofibers, and thereafter collecting the attenuated fibers. An exemplarymeltblowing process is taught in, for example, U.S. Pat. No. 6,607,624.

The ionic liquid material can be applied to the nonwoven fibrousstructure 234 at different stages of each of the forming methods. Insome exemplary embodiments, as described herein, the ionic liquidmaterial can be applied to fibers and/or filaments during a formation(e.g., in a forming chamber, etc.) of the fibers and/or filamentsutilizing a mist process to spray the fibers and/or filaments while theyare being collected on a collector. In some exemplary embodiments, asdescribed herein, the ionic liquid material can be applied to thenonwoven fibrous structure 234 once the fibers and/or filaments arecollected on a collector. In this embodiment, the ionic liquid materialcan be applied by known processing means such as roll coating, spraycoating, and immersion coating and combinations of these coatingtechniques.

Nonwoven fibrous structures of the present disclosure and filter mediaincluding the same may, in some exemplary embodiments, advantageouslyincorporate a biodegradable material, a particulate material, a framematerial, or a combination thereof. Some filter media incorporatingbiodegradable material (e.g. polyhydroxy alkonates (PHA),polyhydroxybutyrates (PHB), and the like) may, at the end of theiruseful life, be disposed of advantageously in municipal land-fills orindustrial composting sites, thereby eliminating the need to return orotherwise recycle the spent filter media.

The operation of various embodiments of the present disclosure will befurther described with regard to the following detailed Examples.

EXAMPLES

These Examples are merely for illustrative purposes and are not meant tobe overly limiting on the scope of the appended claims. Notwithstandingthat the numerical ranges and parameters setting forth the broad scopeof the present disclosure are approximations, the numerical values setforth in the specific examples are reported as precisely as possible.Any numerical value, however, inherently contains certain errorsnecessarily resulting from the standard deviation found in theirrespective testing measurements. At the very least, and not as anattempt to limit the application of the doctrine of equivalents to thescope of the claims, each numerical parameter should at least beconstrued in light of the number of reported significant digits and byapplying ordinary rounding techniques.

Test Methods

Testing of the formed nonwoven fibrous webs was carried out using thetesting apparatus listed in Table I, according to the methods describedfurther below. In all testing procedures, a standard reference sample(i.e., comparative example), denoted “Std.” was measured for comparison.The standard reference samples (i.e., comparative examples) consisted ofthe corresponding web coated with binder only and no ionic liquidadditive.

TABLE I Testing Apparatus Apparatus Supplier Balance Mettler Toledo,Inc. Instron 5965 Instron Instruments, Inc.

Basis Weight

The basis weight of the nonwoven webs was measured with a Mettler ToledoXS4002S electronic balance.

Tensile Strength and Percent Elongation

Tensile strength and percent (%) elongation measurements were carriedout on nonwoven samples (15×2.5 cm) on an Instron 5965 machine with amaximum load of 100N. For each nonwoven sample, three samples weremeasured and the average obtained.

Raw Materials

Unless otherwise noted, all parts, percentages, ratios, etc. in theExamples and the rest of the specification are by weight. Solvents andother reagents used may be obtained from Sigma-Aldrich Chemical Company(Milwaukee, Wis.) unless otherwise noted. In addition, Table II providesabbreviations and a source for all materials used in the Examples below:

TABLE II Raw Materials Raw Material Supplier Acrodur 3530 BASF FranceS.A.S. OC Biobinder Organoclick AB Sweden Rhoplex B-15RH Emulsion Rohmand Haas Europe Trading APS Latex Plextol SB310 Synthomer PEG 400 DowChemical Ionic liquids Iolitec GmbH Larostat HTS 905 BASF GmbH ViscoseFibers (40 mm, 1.7 dTex) Lenzing AG Polyester Fibers (20 denier)Palmetto Synthetics LLC Nylon Fibers (HT) EMS-GRILTECH Melty Fibers (20denier) Huvis

In the following examples, “IL” denotes ionic liquid, “PET” denotespolyester, “MD” denotes machine direction, “TD” denotes transversedirection (relative to MD), “TS” denotes tensile strength, “elong”denotes percentage elongation, “PEG” denotes polyethylene glycol, “Std.”denotes a reference standard (i.e., a comparative example).

Binders

Acrodur 3530 (50% Solids Approx.):

Unless otherwise stated this binder was coated on the nonwoven web byroll coating pre-diluted in the ratio of 2:1 with H₂O (33% solidsapprox.). The binder was then cured in a through air oven at 140° C. forapprox. 4 minutes.

OC Biobinder (15% Solids Approx.):

Unless otherwise stated this binder was coated on the nonwoven web byroll coating pre-diluted in the ratio of 2:1 with H₂O. The binder wasthen cured in a through air oven at 130° C. for approx. 4 minutes.

Ionic Liquids

The ionic liquids (IL) listed in Table III were added at 10% w/v to thebinder aqueous solutions. The ionic liquids were added in one part tothe binder aqueous solution and stirred until fully dissolved.

TABLE III Ionic Liquids (IL) Ionic Liquid Reference Code Chemical NameIL A 1-ethyl-3-methylimidazolium diethyl phosphate IL B1-ethyl-3-methylimidazolium ethyl sulfate IL C1-ethyl-3-methylimidazolium acetate IL I 1-ethyl-3-methylimidazoliumtriflate IL L 1-ethyl-3-methylimidazolium dicyanamide IL OTrihexyltetradecylphosphonium chloride IL E1 Choline dihydrogenphosphate IL H1 1-ethyl-3-methylimidazolium chloride IL I1 Larostat HTS905 IL J1 1-butyl-3-methylimidazolium chloride IL K1Ethyltributylphosphonium diethyl phosphate IL M1 1,3-dimethylimidazoliumdimethyl phosphate IL N1 1-ethyl-3-methylimidazolium dimethyl phosphateIL O1 1-butyl-3-methylimidazolium dimethyl phosphate IL P11,3-diethylimidazolium diethyl phosphate

Fibers

Mixtures of fibers as listed in Table IV (i.e., viscose, PET, nylon)with low melting fibers were formed in a ratio of 80:20 fiber:lowmelting fiber ratio, and processing of the fiber mixtures was carriedout using the nonwoven processing equipment listed in Table V.

TABLE IV Fibers Prebond Web Basis Weight Fiber Prebond Web (g/m²)Viscose 80 PET 70 Nylon 95

TABLE V Nonwoven Processing Equipment Machine Supplier Fiber OpenerLaroche Rando Webber Rando Machine Corporation Roll Coater Cavitec

Web Formation

Fiber prebonded webs were formed prior to coating of the resins. Therequired ratio of fibers to melty fibers were weighed and mixed bypassing through a fiber opener. The air-laid prebonded webs were formedon a Rando Webber forming machine. Following forming of the web, it wassent through a through-air oven at 130° C. to yield a lightly bonded websuitable for coating trials.

Web Consolidation

The prebonded webs were coated by passing through roll coating cylinderscontaining the binder/ionic liquid mixture in the reservoir.

Example 1

Tables 1-4 show the Tensile Test results for nonwoven viscose prebondwebs with Acrodur binder and with various ionic liquids.

TABLE 1 Tensile Acrodur Binder Strength (MD) with IL TS - MD TS - MDTS - MD Average IT1 Std. 3.44 3.59 3.44 3.49 IT2 PEG 400 3.81 3.71 3.53.67 IT3 ILA 4.28 4.01 3.93 4.07 IT4 ILB 2.71 2.56 2.56 2.61 IT5 ILC 4.23.25 3.88 3.78 IT6 ILI 3.62 2.89 3.27 3.26 IT7 ILL 4.25 2.58 4.08 3.64

TABLE 2 Acrodur Binder Elongation - Elongation - Elongation -Elongation - with IL MD MD MD MD Average IT1 Std. 2.92 1.82 2.65 2.46IT2 PEG 400 9.25 10.9 11.17 10.44 IT3 ILA 6.73 6.77 7.87 7.12 IT4 ILB6.22 6.5 6.77 6.50 IT5 ILC 4.57 2.65 4.3 3.84 IT6 ILI 4.85 3.47 3.754.02 IT7 ILL 2.64 1.27 1.82 1.91

TABLE 3 Acrodur Binder TS - TD with IL TS - TD TS - TD TS - TD AverageIT1 Std. 2.66 2.78 2.63 2.69 IT2 PEG 400 2.69 2.7 3.39 2.93 IT3 ILA 2.192.61 1.47 2.09 IT4 ILB 2.55 2.76 2.54 2.62 IT5 ILC 1.67 1.96 1.8 1.81IT6 ILI 1.92 1.82 1.71 1.82 IT7 ILL 2.5 2.17 2.93 2.53

TABLE 4 Acrodur Binder Elongation - Elongation - Elongation -Elongation - with IL TD TD TD TD Average IT1 Std. 2.37 2.65 2.37 2.46IT2 PEG 400 11.72 12 14.75 12.82 IT3 ILA 3.2 4.02 2.65 3.29 IT4 ILB 1213.92 11.17 12.36 IT5 ILC 4.02 4.85 4.85 4.57 IT6 ILI 4.57 5.12 4.3 4.66IT7 ILL 1.82 1.55 2.1 1.82

Tables 5-8 show the Tensile Test results for nonwoven viscose prebondwebs with OC Biobinder binder and various ionic liquids.

TABLE 5 OC Biobinder TS - MD Binder with IL TS - MD TS - MD TS - MDAverage IT9 Std. 3.66 3.36 3.21 3.41 IT10 PEG 400 2.52 2.24 2.33 2.36IT11 ILA 2 1.91 2 1.97 IT12 ILB 2.17 2.32 2.39 2.29 IT13 ILC 1.44 1.291.31 1.35 IT14 ILI 3.27 2.65 3.16 3.03 IT15 ILL 2.48 2.15 2.13 2.25 IT16IL0 2.43 2.49 2.49 2.47

TABLE 6 OC Biobinder Elongation - Elongation - Elongation - Elongation -Binder with IL MD MD MD MD Average IT9 Std. 3.75 3.47 4.3 3.84 IT10 PEG400 3.75 2.65 3.47 3.29 IT11 ILA 9.25 7.32 6.77 7.78 IT12 ILB 8.97 7.879.52 8.79 IT13 ILC 14.2 15.02 15.3 14.84 IT14 ILI 4.02 4.3 3.75 4.02IT15 ILL 10.35 9.8 4.27 8.14 IT16 IL0 5.12 3.75 4.3 4.39

TABLE 7 OC Biobinder TS - TD Binder with IL TS - TD TS - TD TS - TDAverage IT9 Std. 2.28 2.17 2.22 2.22 IT10 PEG 400 1.41 1.21 1.24 1.29IT11 ILA 1.13 1.16 1.03 1.11 IT12 ILB 1.64 1.6 1.48 1.57 IT13 ILC 0.60.62 0.56 0.59 IT14 ILI 2.01 1.78 1.78 1.86 IT15 ILL 1.29 1.13 1.03 1.15IT16 IL0 1.55 1.66 1.65 1.62

TABLE 8 OC Biobinder Elongation - Elongation - Elongation - Elongation -Binder with IL TD TD TD TD Average IT9 Std. 4.02 4.3 4.3 4.21 IT10 PEG400 4.02 3.2 2.92 3.38 IT11 ILA 10.35 9.25 10.62 10.07 IT12 ILB 7.878.15 8.42 8.15 IT13 ILC 12 14.75 14.47 13.74 IT14 ILI 4.57 4.02 3.474.02 IT15 ILL 8.97 8.7 6.77 8.15 IT16 IL0 5.67 5.67 5.12 5.49

Example 2

Tables 9-12 show the Tensile Test results for nonwoven viscose prebondwebs with Acrodur binder and various ionic liquids.

TABLE 9 Acrodur Binder TS - MD with IL TS - MD TS - MD TS - MD Average 1Std. 3.11 3.12 2.71 2.98 2 PEG 5.16 4.43 4.45 4.68 3 ILE1 3.91 4.7 4.784.46 4 ILH1 3.86 3.55 3.64 3.68 5 IL I1 4.28 3.64 3.07 3.66

TABLE 10 Acrodur Elongation - Elongation - Elongation - Elongation -Binder with IL MD MD MD MD Average 1 Std. 1.55 1.55 1.27 1.46 2 PEG 4.025.67 3.75 4.48 3 ILE1 1.82 2.1 2.1 2.01 4 ILH1 8.42 6.77 4.85 6.68 5 ILI1 2.65 2.37 1.55 2.19

TABLE 11 Acrodur TS - TD Binder with IL TS - TD TS - TD TS - TD Average1 Std. 2.6 2.78 2.53 2.64 2 PEG 3.54 3.75 3.57 3.62 3 ILE1 3.08 3.223.53 3.28 4 ILH1 2.58 2.11 3.2 2.63 5 IL I1 2.91 2.43 2.62 2.65

TABLE 12 Acrodur Elongation - Elongation - Elongation - Elongation -Binder with IL TD TD TD TD Average 1 Std. 1.27 1.27 1.27 1.27 2 PEG 8.428.15 8.7 8.42 3 ILE1 2.1 2.37 2.1 2.19 4 ILH1 4.57 3.47 8.15 5.40 5 ILI1 2.37 1.82 2.37 2.19

Tables 13-16 show the Tensile Test results for nonwoven viscose prebondwebs with OC Biobinder binder and various ionic liquids.

TABLE 13 OC Biobinder TS - MD Binder with IL TS - MD TS - MD Average 1Std. 2.89 3.29 3.09 2 PEG 2.16 2.2 2.18 3 ILE1 2.86 2.47 2.67 4 ILH12.14 2.33 2.24 5 IL I1 2.4 2.43 2.42

TABLE 14 OC Biobinder Elongation - Elongation - Elongation - Binder withIL MD MD MD Average 1 Std. 1.82 2.37 2.10 2 PEG 3.47 4.3 3.89 3 ILE18.15 7.32 7.74 4 ILH1 12 12 12.00 5 IL I1 5.95 7.23 6.59

TABLE 15 OC Biobinder TS - TD Binder with IL TS - TD TS - TD Average 1Std. 2.14 2.63 2.39 2 PEG 1.89 1.82 1.86 3 ILE1 2 2.28 2.14 4 ILH1 1.031.06 1.05 5 IL I1 1.85 1.75 1.80

TABLE 16 OC Biobinder Elongation - Elongation - Elongation - Binder withIL TD TD TD Average 1 Std. 2.1 2.92 2.51 2 PEG 3.75 4.3 4.03 3 ILE1 5.127.05 6.09 4 ILH1 11.45 18.32 14.89 5 IL I1 6.5 6.77 6.64

Example 3

Tables 17-18 show the Tensile Test results for nonwoven viscose prebondwebs with Primal B15 binder and various ionic liquids.

TABLE 17 Primal B15 TS - MD Binder with IL TS - MD TS - MD TS - MDAverage Std. 3.39 3.7 3.68 3.59 ILA 2.05 1.6 1.49 1.71 ILB 2.12 1.651.86 1.88 ILC 1.98 1.58 1.88 1.81 ILH1 2.07 1.57 1.73 1.79 ILI1 0.780.95 0.98 0.90

TABLE 18 Primal B15 Elongation - Elongation - Elongation - Elongation -Binder with IL MD MD MD MD Average Std. 23.55 27.95 25.75 25.75 ILA32.35 32.07 32.62 32.35 ILB 27.95 26.57 27.67 27.40 ILC 32.62 27.67 32.931.06 ILH1 31.25 22.72 30.7 28.22 ILI1 41.7 37.3 43.07 40.69

Example 4

The nonwoven samples tested consisted of viscose prebond webs. Tables19-22 show the Tensile Test results for Example 4 with various ionicliquids.

TABLE 19 Latex Plextol TS - MD Binder with IL TS - MD TS - MD TS - MDAverage Std. 5.44 4.54 4.54 4.84 IL B 4.22 2.95 3.67 3.61 IL C 3.28 3.33.11 3.23 IL I 2.61 2.47 2.69 2.59 IL L 3.54 3.21 3.29 3.35 IL I1 0.970.92 0.78 0.89 IL H1 1.89 2.2 1.97 2.02

TABLE 20 Latex Plextol Elongation - Elongation - Elongation -Elongation - Binder with IL MD MD MD MD Average Std. 16.4 10.9 12.2713.19 IL B 15.85 16.94 18.04 16.94 IL C 26.06 23.82 24.64 24.84 IL I11.99 11.99 11.44 11.81 IL L 19.15 18.32 19.15 18.87 IL I1 7.32 7.596.77 7.23 IL H1 14.47 18.32 16.67 16.49

TABLE 21 Latex Plextol TS - TD Binder with IL TS - TD TS - TD TS - TDAverage Std. 4.23 4.53 4.39 4.38 IL B 2.63 2.46 2.09 2.39 IL C 2.07 1.862.24 2.06 IL I 3.54 3.71 3.3 3.52 IL L 1.44 1.43 1.61 1.49 IL I1 0.740.84 0.77 0.78 IL H1 2.28 1.87 1.66 1.94

TABLE 22 Latex Plextol Elongation - Elongation - Elongation -Elongation - Binder with IL TD TD TD TD Average Std. 15.3 13.92 15.314.84 IL B 22.72 18.87 17.49 19.69 IL C 28.22 25.74 25.19 26.38 IL I17.49 16.94 15.84 16.76 IL L 21.62 18.12 24.09 21.28 IL I1 6.22 6.496.77 6.49 IL H1 23.54 21.64 22.72 22.63

Example 5

The nonwoven samples tested consisted of viscose prebond webs. Tables23-24 show the Tensile Test results for Example 5 with various ionicliquids.

TABLE 23 Acrodur TS - MD Binder with IL TS - MD TS - MD TS - MD AverageStd. 3.1 3.05 2.97 3.04 IL J1 3.39 3.4 3.29 3.36 IL K1 3.2 2.63 2.952.93 IL M1 2.6 2.99 3.07 2.89 IL N1 3.39 2.65 3.42 3.15 IL O1 3.11 2.792.78 2.89 IL P1 3.25 3.21 3.78 3.41

TABLE 24 Primal B15 Elongation - Elongation - Elongation - Elongation -Binder with IL MD MD MD MD Average Std. 1.55 1.55 1.55 1.55 IL J1 4.854.02 3.75 4.21 IL K1 2.37 1.82 1.82 2.00 IL M1 2.92 2.92 2.92 2.92 IL N13.75 2.37 2.65 2.92 IL O1 2.92 2.65 2.1 2.56 IL P1 2.37 2.65 2.92 2.65

Surface Resistivity Test Results

The surface resistivity of the nonwoven coated samples was carried outaccording to VDE 0303 part 30. The test equipment consisted of aTeraohmmeter (PM 126 567), electrode (20 cm²) and Å Electrode (5 cm).The following terms are defined for the Surface Resistivity Test:

σ [Ω] surface resistivity Rx [Ω] measured surface resistivity p [cm]effective scope of the protected electrode g [cm] distance between theelectrodes

Example 1

Tables 25-32 show the Surface Resistivity Test results for Example 1with various ionic liquids.

TABLE 25 Sample Ref. Rx Avg. Latex Plextol Std. 5 2.E+09 IL A 6 3.E+05IL C 7 1.E+06 IL I 8 1.E+08 IL L 9 2.E+05 IL I1 10 2.E+05 IL H1 117.E+05

TABLE 26 Rx σ Voltage Sample [Ω] [Ω] [V] 5 1.35E+08 2.16E+10 5004.47E+09 7.16E+11 500 2.48E+09 3.97E+11 500

TABLE 27 Rx σ Voltage Sample [Ω] [Ω] [V] 6 6.35E+05 1.02E+08 1001.54E+05 2.47E+07 100 1.68E+05 2.70E+07 100

TABLE 28 Rx σ Voltage Sample [Ω] [Ω] [V] 7 9.96E+05 1.60E+08 1001.65E+05 2.64E+07 100 2.03E+06 3.24E+08 100

TABLE 29 Rx σ Voltage Sample [Ω] [Ω] [U] 8 1.88E+08 3.01E+10 5007.78E+07 1.25E+10 500 3.69E+07 5.91E+09 500

TABLE 30 Rx σ Voltage Sample [Ω] [Ω] [V] 9 2.59E+05 4.15E+07 1001.84E+05 2.95E+07 100 2.55E+05 4.09E+07 100

TABLE 31 Rx σ Voltage Sample [Ω] [Ω] [V] 10 3.92E+05 6.28E+07 101.84E+05 2.95E+07 10 1.23E+05 1.96E+07 10

TABLE 32 Rx σ Voltage Sample [Ω] [Ω] [V] 11 2.00E+05 3.20E+07 1001.13E+06 1.81E+08 100 7.06E+05 1.13E+08 100

Example 2

Tables 33-43 show the Surface Resistivity Test results for Example 2with various ionic liquids.

TABLE 33 Sample Ref. Rx Avg. Acrodur Std. 12 4.E+09 PEG 13 3.E+08 E1 142.E+08 H1 15 2.E+07 I1 16 7.E+08 OC BioBinder Std. 17 7.E+08 PEG 186.E+06 E1 19 3.E+05 H1 20 2.E+04 I1 21 1.E+06

TABLE 34 Rx σ Voltage Sample [Ω] [Ω] [V] 12 4.22E+09 6.76E+11 5003.92E+09 6.27E+11 500 2.91E+09 4.67E+11 500

TABLE 35 Rx σ Voltage Sample [Ω] [Ω] [V] 13 4.53E+08 7.25E+10 5002.95E+08 4.72E+10 500 2.00E+08 3.21E+10 500

TABLE 36 Rx σ Voltage Sample [Ω] [Ω] [V] 14 2.11E+08 3.38E+10 5001.38E+08 2.20E+10 500 1.28E+08 2.05E+10 500

TABLE 37 Rx σ Voltage Sample [Ω] [Ω] [V] 15 2.49E+07 3.99E+09 5002.13E+07 3.42E+09 500 1.97E+07 3.16E+09 500

TABLE 38 Rx σ Voltage Sample [Ω] [Ω] [V] 16 1.13E+09 1.82E+11 5005.18E+08 8.30E+10 500 5.10E+08 8.16E+10 500

TABLE 39 Rx σ Voltage Sample [Ω] [Ω] [V] 17 1.04E+09 1.66E+11 5006.73E+08 1.08E+11 500 5.06E+08 8.11E+10 500

TABLE 40 Rx σ Voltage Sample [Ω] [Ω] [V] 18 4.84E+06 7.75E+08 5004.90E+06 7.85E+08 500 7.02E+06 1.12E+09 500

TABLE 41 Rx σ Voltage Sample [Ω] [Ω] [V] 19 2.53E+05 4.05E+07 1002.32E+05 3.71E+07 100 3.86E+05 6.18E+07 100

TABLE 42 Rx σ Voltage Sample [Ω] [Ω] [V] 20 1.73E+04 2.78E+06 102.27E+04 3.64E+06 10 8.08E+03 1.29E+06 10

TABLE 43 Rx σ Voltage Sample [Ω] [Ω] [V] 21 1.31E+06 2.10E+08 5001.17E+06 1.87E+08 500 8.74E+05 1.40E+08 500

Example 3

Tables 44-51 show the Surface Resistivity Test results for Example 3with various ionic liquids.

TABLE 44 Sample Ref. Rx Avg. Acrodur Std. 22 2.E+09 PEG 23 2.E+08 A 241.E+08 B 25 4.E+07 C 26 1.E+08 I 27 5.E+06 L 28 1.E+09

TABLE 45 Rx σ Voltage Sample [Ω] [Ω] [V] 22 1.51E+09 2.42E+11 5001.67E+09 2.68E+11 500 1.62E+09 2.59E+11 500

TABLE 46 Rx σ Voltage Sample [Ω] [Ω] [V] 23 1.26E+08 2.02E+10 5001.96E+08 3.14E+10 500 1.63E+08 2.61E+10 500

TABLE 47 Rx σ Voltage Sample [Ω] [Ω] [V] 24 1.47E+08 2.35E+10 5001.73E+08 2.77E+10 500 1.23E+08 1.97E+10 500

TABLE 48 Rx σ Voltage Sample [Ω] [Ω] [V] 25 5.03E+07 8.05E+09 5005.33E+07 8.54E+09 500 2.65E+07 4.24E+09 500

TABLE 49 Rx σ Voltage Sample [Ω] [Ω] [V] 26 1.17E+08 1.88E+10 5001.50E+08 2.40E+10 500 1.24E+08 1.98E+10 500

TABLE 50 Rx σ Voltage Sample [Ω] [Ω] [V] 27 7.23E+06 1.16E+09 5005.02E+06 8.05E+08 500 2.61E+06 4.18E+08 500

TABLE 51 Rx σ Voltage Sample [Ω] [Ω] [V] 28 1.63E+09 2.62E+11 5001.22E+09 1.95E+11 500 1.06E+09 1.70E+11 500

Flame Retardancy Test Results

Flame retardancy testing was carried out according to test method UL94vertical burner test procedure with minor modifications. Methane gas ata pressure of 2.5 psi was used for the Bunsen burner. The flame coneheight measurements were as follows: 1 cm for the interior and 2 cm forthe exterior. The distance between the Bunsen tip and the end of thesample was 1 cm. The sample size was 15×2.5 cm. The sample measuredconsisted of a web of viscose fibers with the requisite bindercontaining 10% ionic liquid unless otherwise stated. 3 samples weremeasured for each binder/IL combination. When all 3 samples gave thesame results, only 1 overall result is noted.

T1: Duration (seconds) of after flame after ignited Bunsen was appliedto sample for 10 secondsT2: After flame following application of Bunsen for a further 10 secondsT3: After flame following application of Bunsen for a further 10 secondsB: Sample burnedNote: When after flame exposure result is equal to zero, this the sampleresisted ignition.

Table 52 shows the Flame Retardancy Test results for Example 2 withvarious binders and ionic liquids.

TABLE 52 Binder IL T1 T2 T3 OC Biobinder No IL - Standard B — — OCBiobinder E1 0 0 0 OC Biobinder H1 B — — OC Biobinder I1 B — — OCBiobinder K1 0 B — B — — B — — OC Biobinder K1 30% 0 0 0 OC Biobinder M1B — — OC Biobinder M1 30% 0 B — 0 B — 0 0 0 OC Biobinder N1 0 B — B — —B — — OC Biobinder N1 30% 0 B — B — — B — — OC Biobinder O1 0 B — 0 B —0 0 0 OC Biobinder O1 30% 0 0 B B — — 0 — — OC Biobinder P1 0 B — B — —B — — OC Biobinder P1 30% 0 0 0 0 B — 0 0 0 Acrodur No IL - Standard B —— Acrodur E1 0 0 0 Acrodur H1 0 0 0 0 B — B — — Acrodur K1 0 0 0 0 B — 0B — Acrodur M1 0 0 0 x — — x — — Acrodur N1 x — — 0 0 0 0 0 0 Acrodur O10 0 0 Acrodur P1 0 X —

Table 53 summarizes overall performance properties with respect toTensile Strength, Anti-static properties, and Flame Retardancy.

TABLE 53 Multi-functional Ionic Liquids - Performance SummaryImprovements Flame IL Binder TS Elongation Anti-static Retardancy AAcrodur + + + B Acrodur + + C Acrodur + + + I Acrodur + + L Acrodur + +E1 Acrodur + + + + H1 Acrodur + + + I1 Acrodur + + + J1 Acrodur + + K1Acrodur + + M1 Acrodur + + N1 Acrodur + + + O1 Acrodur + + P1Acrodur + + + A OC Biobinder + B OC Biobinder + C OC Biobinder + I OCBiobinder + L OC Biobinder + E1 OC Biobinder + + + H1 OC Biobinder + +I1 OC Biobinder + + J1 OC Biobinder + K1 OC Biobinder + + M1 OCBiobinder + + N1 OC Biobinder + O1 OC Biobinder + + P1 OC Biobinder + +Sample tested + Sample tested and demonstrated improvement in comparisonto the control standard

Reference throughout this specification to “one embodiment,” “certainexemplary embodiments,” “one or more embodiments” or “an embodiment,”whether or not including the term “exemplary” preceding the term“embodiment,” means that a particular feature, structure, material, orcharacteristic described in connection with the embodiment is includedin at least one embodiment of the certain exemplary embodiments of thepresent disclosure. Thus, the appearances of the phrases such as “in oneor more embodiments,” “in certain exemplary embodiments,” “in oneembodiment” or “in an embodiment” in various places throughout thisspecification are not necessarily referring to the same embodiment ofthe certain exemplary embodiments of the present disclosure.Furthermore, the particular features, structures, materials, orcharacteristics may be combined in any suitable manner in one or moreembodiments.

While the specification has described in detail certain exemplaryembodiments, it will be appreciated that those skilled in the art, uponattaining an understanding of the foregoing, may readily conceive ofalterations to, variations of, and equivalents to these embodiments.Accordingly, it should be understood that this disclosure is not to beunduly limited to the illustrative embodiments set forth hereinabove.

Furthermore, all publications and patents referenced herein areincorporated by reference in their entirety to the same extent as ifeach individual publication or patent was specifically and individuallyindicated to be incorporated by reference. Various exemplary embodimentshave been described. These and other embodiments are within the scope ofthe following claims.

1. A method of making a nonwoven fibrous structure, comprising:introducing a plurality of fibers into a forming chamber; dispersing thefibers within the forming chamber to form a population of individualfibers suspended in a gas; collecting the population of fibers as anonwoven fibrous structure on a collector; and bonding at least aportion of the population of fibers together with an ionic reinforcementmaterial.
 2. The method of claim 1, further comprising applying an ionicliquid material to the population of fibers, optionally wherein bondingat least the portion of the population of fibers together comprisescuring the applied ionic liquid material to form the ionic reinforcementmaterial. 3-4. (canceled)
 5. The method of claim 2, wherein the appliedionic liquid material further comprises at least one binder resin,optionally wherein the applied ionic liquid material acts as aplasticizer for the at least one binder resin, optionally wherein the atleast one binder resin is selected from the group consisting of aphenolic resin, a bio-based resin, a thermoplastic (meth)acrylic(co)polymer resin, an epoxy resin, or a combination thereof. 6-7.(canceled)
 8. The method of claim 2, wherein the ionic liquid materialcomprises at least one cation and at least one anion.
 9. The method ofclaim 2, wherein the at least one cation is selected from the groupconsisting of nitrogen containing heterocyclic cations, ammonium,phosphonium, or sulfonium; and further wherein the at least one anion isselected from the group consisting of halogen anions, fluorinecontaining anions, alkyl sulfate anions, alkyl phosphate anions,acetate, dicyanamide (N(CN)₂), or thiocyanate (SCN).
 10. The method ofclaim 2, wherein applying the ionic liquid material consists of sprayingthe ionic liquid material, roll coating the ionic liquid material, dipcoating the ionic liquid material, or a combination thereof. 11-19.(canceled)
 20. A nonwoven fibrous structure comprising: a population ofrandomly oriented fibers bonded together at a plurality of intersectionpoints with an ionic reinforcement material.
 21. The nonwoven fibrousstructure of claim 20, wherein the ionic reinforcement material iscomprised of an ionic plasticizer.
 22. The nonwoven fibrous structure ofclaim 20, wherein the ionic reinforcement material is comprised of anionic liquid and a binder selected from the group consisting of a(meth)acrylic (co)polymer binder, a styrene-butadiene latex binder, abio-based binder, or a combination thereof.
 23. The nonwoven fibrousstructure of claim 22, comprising from 1 to 40 wt. % of the ionicliquid.
 24. The nonwoven fibrous structure of claim 22, wherein theionic liquid comprises water, one or more cations, and one or moreanions.
 25. The nonwoven fibrous structure of claim 20, exhibiting atleast one distinguishing characteristic selected from the groupconsisting of a fire retardant characteristic, an antistaticcharacteristic, an antibacterial characteristic, an antimicrobialcharacteristic, an antifungal characteristic, or a combination thereof.26-27. (canceled)
 28. The nonwoven fibrous structure of claim 20,wherein the population of fibers includes fibers selected from the groupconsisting of mono-component fibers, multi-component fibers, crimpedfibers, or a combination thereof.
 29. The nonwoven fibrous structure ofclaim 20, wherein the population of fibers includes fibers selected fromthe group consisting of staple fibers, melt blown fibers, naturalfibers, or a combination thereof.
 30. The nonwoven fibrous structure ofclaim 20, wherein the population of fibers includes thermoplastic(co)polymer fibers further comprising a (co)polymer selected frompoly(propylene), poly(ethylene), poly(butane), poly(ethylene)terephthalate, poly(butylene) terephthalate, poly(ethylene) napthalate,poly(amide), poly(urethane), poly(lactic acid), poly(vinyl)alcohol,poly(phenylene) sulfide, poly(sulfone), liquid crystalline polymer,poly(ethylene)-co-poly(vinyl)acetate, poly(acrylonitrile), cyclicpoly(olefin), poly(oxymethylene), poly(olefinic) thermoplasticelastomers, recycled fibers containing any of the precedingthermoplastic (co)polymers, or a combination thereof.
 31. The nonwovenfibrous structure of claim 20, wherein the population of fibers includesnatural fibers selected from cotton, wool, jute, agave, sisal, coconut,soybean, hemp, viscose, bamboo, or a combination thereof.
 32. Thenonwoven fibrous structure of claim 20, wherein the nonwoven fibrousstructure includes a population of particulates bonded to the nonwovenfibrous structure, further wherein the particulates are selected fromthe group consisting of abrasive particulates, detergent particulates,anti-bacterial particulates, adsorbent particulates, absorbentparticulates; or a combination thereof.
 33. The nonwoven fibrousstructure of claim 20, wherein the population of particulates exhibits amedian particle diameter of from 0.1 micrometer to 1,000 micrometers.34. The nonwoven fibrous structure of claim 20, wherein the populationof fibers exhibits a median fiber diameter of from 1 micrometer to 50micrometers.
 35. The nonwoven fibrous structure of claim 20, wherein thenonwoven fibrous structure is a structure selected from the groupconsisting of a mat, a web, a sheet, a scrim, or a combination thereof.